Can you/has anyone rolled 12v (12AX7) tubes in their Dodd Tube Buffer preamp? Mine came with a 6DJ8 family tube, which I have rolled a few of, but there is also a 6v-12v selector switch that I have never tried. I know the Dodd buffers used in the Sensation Audio gear come stock with a 12AX7, but never seen a discussion of this.